Field of the Invention
This invention relates in general to electrical furnaces and in particular to new and useful electrode and coolant line assembly which may be easily connected or disconnected from each other and from the furnace.
The invention relates particularly to a contact electrode arrangement for direct current arc or resistance melting furnaces comprising a support plate, with a base plate disposed at a distance therefrom with contact rods attached thereto as well as current and cooling medium lines also attached thereto.
The design and operation of similar furnaces is known. A contact electrode arrangement is described specifically in DE-PS No. 31 06 741. Further, reference is made to German patent application No. P 35 35 692.8, in which an exchangeable contact electrode assembly is described. This assembly comprises the complete contact electrode and support plate, base plate, contact devices (contact rods) as well as current cables and cooling medium conduits mounted on the base plate. The contact electrode is a tamped refractory material made with a template as a block and, as an exchangeable assembly, is lowered by hoists into an opening in the furnace tank floor, so that the contact electrode rests with its support plate on the edge of the furnace tank floor. The annular gap between the furnace floor lining and the contact electrode is tamped. The current cables and coolant conduits are disposed on attachment elements.
When after a respective operating time the contact rods are used up, instead of changing individual contact rods, according to the patent application the complete contact electrode assembly is detached by means of pressure elements from its seat in the furnace tank floor and lifted and thereafter extracted upwardly from the furnace tank by hoists which are fitted on support means of the contact electrode assembly.
To prepare the contact electrode change, the current cables and coolant conduits must be taken off the attachments of the contact electrode. The drawback of this procedure is that the current cables and also the coolant conduits are difficult to handle due to their weight. If large melting furnance units are involved, even special assembly and disassembly equipment is needed for this work. Besides, the ergonomic conditions in the respective work zone are very unfavorable, as the heat radiation of the melting furnace makes work difficult for the personnel. It is the object of the invention to simplify the attaching of the current cables and coolant conduits at the contact electrode, to accelerate it and to improve it in ergonomic respect.